My initial first impressions are that the fit and finish is excellent (38 sport white).
The haptic feedback was slight at first, but after turning on prominent haptic it's fine.
The packaging, while heavy, is very high quality -- and this is just based off the sport model. Definitely the best packaging of any apple product in a long time.
Third party apps such as instagram do take a while to load. The first party apps are quick and snappy.
I have yet to test the fitness capabilities, but I expect them to be fine.
Basically, I think the phone works exactly as advertised and I'm satisfied.
That being said, I'm still glad I only purchased the sport. The watch definitely has a generation one feel to it and a watch operable independent from an iphone has to be the next iteration, along with more health functions (such as bp). For myself, I'm not entirely sure how the watch will be incorporated in my life. I don't know if it will truly enhance anything or make things more streamlined and simpler. It is, however, very cool. That might be all it needs right now.